[PATCH] PPC64 Use hardware sqrt.

[Kumar Gala]

Tom,

I'm confused, the --nf option is for PPC32 w/o any floating point, or 
PPC32 w/floating point but not the optional instructions?

- kumar

On Apr 30, 2004, at 9:51 PM, Tom Gall wrote:

> Kumar Gala wrote:
>
>> Understand, but future PPC64 from Freescale (former Motorola SPS) are 
>> unlikely to implement it.
>
> If they do then likely they will also leave the other optional 
> floating point operations unimplemented and in that case the correct 
> way to build glibc is with the --nf option which is already the case 
> for PPC32 processors without floating point. If the processor has all 
> the other optional floating point instructions except sqrt, then I'd 
> say that design needs to be revisited. Historically the optional 
> floating point instructions are either all there (as is the case with 
> ALL ppc64 processors ever made) or not in which case as pointed out to 
> you the --nf option is for you.
>
> I believe sjmunroe is right and his implementation is sound.
> Regards,
>
> Tom
>
>> - kumar
>>
>> On Apr 30, 2004, at 11:00 AM, Steve Munroe wrote:
>>
>>> Kumar Gala wrote on 04/29/2004 05:55:21 PM:
>>>
>>>> I do not think its fair to say that all future PPC64 processors will
>>>> implement the fsqrt instruction.
>>>>
>>>> - kumar
>>>>
>>>
>>> All server (i/pSeries) and 970 models do and will. The silicon 
>>> required
>>> for this is so small as to be lost in the noise of a modern chip 
>>> design.
>>>
>>> So I will take 3-5X performance gain.
>>>
>>> Steven J. Munroe
>>> Linux on Power Toolchain Architect
>>> IBM Corporation, Linux Technology Center
>>